This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. This is a comparative vaccine study to test which DC-targeting vehicle can elicit the most potent protective immunity against influenza infection. Antibody-mediated immunity is an important immune arm for the prevention of influenza infection. To evaluate the potency of DC-targeting vaccines administered i.d., we employ a current vaccine, Fluzone, as a positive control. Although the main objective of this study is to test HA1-specific humoral responses, we will also test the magnitude and spectrum of HA1-specific cellular responses that are necessary for eliciting potent humoral immunity.